1. Technical Field
The disclosure generally relates to heat transfer apparatuses, and particularly to a heat pipe with high heat transfer efficiency.
2. Description of Related Art
Heat pipes are widely used in various fields for heat dissipation purposes due to their excellent heat transfer performance. One commonly used heat pipe includes a sealed tube made of heat conductive material, with a working fluid contained therein. The working fluid conveys heat from one end of the tube, typically referred to as an evaporator section, to the other end of the tube, typically referred to as a condenser section. Preferably, a wick structure is provided inside the heat pipe, lining an inner wall of the tube, and drawing the working fluid back to the evaporator section after it condenses at the condenser section.
During operation, the evaporator section of the heat pipe maintains thermal contact with a heat-generating electronic component. The working fluid at the evaporator section absorbs heat generated by the electronic component, and thereby turns to vapor. Due to the difference in vapor pressure between the two sections of the heat pipe, the generated vapor moves, carrying the heat with it, toward the condenser section. At the condenser section, the vapor condenses after transferring the heat to, for example, fins thermally contacting the condenser section. The fins then release the heat into the ambient environment. Due to the difference in capillary pressure which develops in the wick structure between the two sections, the condensate is then drawn back by the wick structure to the evaporator section where it is again available for evaporation.
In ordinary use, the heat pipe is flattened to increase a contact area with the electronic component and enable smaller electronic products to incorporate the heat pipe. However, this may downsize a vapor channel of the heat pipe through which the vapor flows from the evaporator section to the condenser section. In such case, the generated vapor may not move toward the condenser section in a timely manner, and the heat transfer efficiency of the heat pipe is thereby reduced.
What is needed, therefore, is a flat heat pipe with a vapor channel which can overcome the described limitations.